For financial reporting purposes, provisions for depreciation are calculated on a straight-line basis over the following estimated useful lives of the underlying assets:
Property, Plant and Equipment ClassificationEstimated Useful Lives
Buildings and improvements
30-40 years
Machinery and equipment
5-15 years
Office equipment and software costs
3-15 years
The “Property, plant and equipment, net” line item in the consolidated statements of financial position, as of December 31, 2025 and 2024, consisted of the following:
(Dollars in millions)20252024
Land and improvements$16.8 $16.1 
Buildings and improvements199.0 189.3 
Machinery and equipment386.2 367.6 
Office equipment and software costs132.0 69.1 
Property plant and equipment, gross734.0 642.1 
Accumulated depreciation(422.1)(390.8)
Property, plant and equipment, net311.9 251.3 
Construction in process60.5 113.8 
Total property, plant and equipment, net$372.4 $365.1 
The depreciation expense and impairment charges related to property, plant and equipment in 2025, 2024 and 2023, were as follows:
(Dollars in millions)202520242023
Depreciation expense$43.3 $37.0 $37.7 
Impairment charges$ $7.9 $— 

Historical Timeline

Fiscal YearFiled
2025Feb 19, 2026Showing above
2024Feb 26, 2025
2023Feb 27, 2024
2022Mar 1, 2023
2021Feb 22, 2022
2020Feb 19, 2021
2019Feb 21, 2020
2018Feb 21, 2019
2017Feb 28, 2018
2016Feb 21, 2017
2015Feb 23, 2016

About PP&E Disclosures

The PP&E disclosure details a company's physical asset base — land, buildings, machinery, and equipment — along with the depreciation methods and useful life assumptions that determine how these costs flow through the income statement. Capitalization policy thresholds reveal management's judgment on the boundary between expense and asset, directly affecting both reported earnings and asset values.

Key signals: changes in estimated useful lives or depreciation methods can materially shift reported earnings without any operational change. Compare capital expenditures against depreciation expense — when capex consistently trails depreciation, the asset base may be aging and underinvested. Watch for large asset impairments or write-downs that signal overvalued carrying amounts. Asset retirement obligations reveal future environmental or decommissioning costs that are often underappreciated. Compare PP&E intensity (PP&E-to-revenue) against industry peers to assess capital efficiency and competitive positioning.